UNDERGRADUATES

GRADUATE STUDENTS

WHY BIOLOGY?

Publication examines quinol oxidase

How do bacteria generate energy in different environmental conditions? Similar to mitochondria, bacteria can generate energy by forming an electron transport chain that ultimately transfers electrons to oxygen. Many bacteria utilize different terminal oxidases to catalyze the final electron transfer to oxygen. A paper recently published by graduate student Zac Lunak and his mentor Dr. Dale Noel provides insight into how a soil bacterium, Rhizobium etli, adjusts to fluctuating oxygen conditions. In this study, they constructed mutants in the different terminal oxidases and analyzed their ability to grow in varying oxygen concentrations. One of these terminal oxidases, the quinol oxidase, is often considered to only be utilized in high oxygen concentrations. Surprisingly, this study found that mutants deficient in this oxidase were unable to efficiently adapt to low oxygen concentrations.